Unsymmetrical dibenzothiophene sulfonate esters are key intermediates in the production of photoactive dibenzothiophene-S-oxide (DBTO) analogs which release ground state atomic oxygen [O(3P)] and are useful for organic light-emitting diodes (OLEDs).1 Dibenzothiophene (DBT) derivatives per their oxidized form as DBTO or dibenzothiophene-S—S-dioxide (DBTOO) have displayed a history of varied photochemistry with the addition of a variety of substituents and different degrees of oxidation about the thiophene sulfur.2 Various symmetrical DBTO derivatives have shown intriguing oxidative capabilities with small organic molecules, and more recently, with biomolecules.3-5 Symmetrical DBTO derivatives have met some limitations in cellular studies prompting the development of unsymmetrical dibenzothiophenes (DBTs). Converting the sulfonate ester of an unsymmetrical DBT to the sulfonic acid salt elicits strong water solubility for an otherwise nonpolar molecule. Previous attempts to develop various dibenzothiophene sulfonic acids without protection of the acid are troublesome as the sensitivities of common carbon-carbon coupling reactions force a less direct synthetic pathway. Thus a need remains for photoactive unsymmetrical DBTs and efficient processes for producing these compounds